Anan ben David, the founder of Karaism--His life, writings, and influence--Hostility to the Talmud--Anan's innovations --Karaite reverence of Anan--The Exilarchate becomes elective--Adoption of Judaism by the Chazars--King Bulan and Isaac Sinjari--Bulan's Jewish successors--Charlemagne and the Empire of the Franks--The Jews and Commerce-- Jewish Envoy sent to the Caliph Haroun Alrashid--Spread of the Jews in Europe--The Caliphs and the Jews--The study of philosophy--Sahal--The Kalam--Mutazilists and Anthropomorphists--Judah Judghan--The _Shiur Komah_--The Akbarites--Moses the Persian. 761-840 C. E. It is as little possible for an historical event to be evolved, as for a natural birth to occur without labor. For a new historical phenomenon to struggle into existence, the comfortable aspect of things must be destroyed, indolent repose in cherished custom disturbed, and the power of habit broken. This destructive activity, although at first painful, is eventually favorable to the growth of healthy institutions, for thereby all vagueness is dissipated, all pretense destroyed, and dim reality brought more clearly to light. Opposition, the salt of history, which prevents corruption, had been wanting in Jewish history for several centuries, and religious life had been molded in set forms, and had there become petrified. Pauline and post-apostolic Christianity in its day supplied just the opposition required. It abrogated the standard of the Law, did away with knowledge, substituted faith, and thus produced in the evolution of Judaism a disposition to cling firmly to the Law, and to develop a system of religious teachings which should deal with the minutest details. The Talmud resulted from this movement of opposition; it was the sole prevailing authority in Judaism, and succeeded in supplanting the Bible in the estimation of the people. Even the study of the Talmud, which had possessed a refreshing and enlightening influence in the time of the Amoraim, had degenerated in the following century and in the first Gaonic period into a mere matter of memory, entirely devoid of any power of intellectual fructification. A free current of air was wanting to clear the heavy atmosphere. Opposition to the Talmud, the password of the two heralds of the Messiah, Serene and Abu-Isa, had left no lasting impression, partly because the movement, accompanied by fanatical agitation in favor of a pretended Messiah, led to no other result than the undeceiving of its partisans, and partly because it had been set on foot by obscure persons, possessed of neither importance nor authority. If this one-sidedness was to be overcome, if the Bible was to be re-instated in its rights, and religious life to regain its spirituality, it was necessary that opposition to it, which up till then had been manifested only in narrow circles, should be imparted to a more extended public by some moderate reformer invested with official character.